Do I need to learn all my LingQs before moving on?

Are you creating too many LingQs to review? Not to worry! You will review most effectively just by reading new lessons

Your most efficient review won't happen using the SRS Review system. Seeing your LingQs again in future lessons or rereading current lessons is a more effective means of review. And, more enjoyable if you study exciting content! Each click on a LingQ in a lesson is another review of that word. Most of your reviewing will happen naturally this way. The main objective is to make a lot of LingQs and keep moving. The words that matter will reappear in future lessons.
If you want to do some review using the activities, go ahead. Sometimes it's nice to mix things up. Or, if you have words that give you trouble, give these a particular tag and then filter for those words on the Vocabulary page so you can review those using the activities. The aim is not to try to drill every word into your brain. Your brain will learn over time. After a month, if you return to the first lesson you did, you will be surprised at how well you now understand.